A Media Gateway Controller (MGC) and a Media Gateway (MG) are two key components of a packet-based network in an architecture where the service function is separated from the bearing function. FIG. 1 is a schematic diagram showing the networking of an MGC and MGs. The MGC is responsible for the service control function, and the MG is responsible for the media bearing function. In this way, the service control plane is separated from the media bearer plane, network resources are shared sufficiently, device upgrade and service extension are simplified, and the costs of development and maintenance are slashed.
The main protocol for communication between the MG and the MGC is a gateway control protocol. Currently, two commonly used gateway control protocols are H.248/MeGaCo and Media Gateway Control Protocol (MGCP), and the H.248/MeGaCo is an evolved version of the MGCP. In the H.248 protocol, various resources on the MG are abstractly expressed as terminations. Terminations are categorized into physical termination and ephemeral termination. A physical termination represents a physical entity of a semi-permanent existence nature, for example, Time Division Multiplex (TDM) timeslots; and an ephemeral termination represents a public resource requested temporarily and released after being used, for example, Real-Time Transport Protocol (RTP) streams. A special termination called “root termination” represents the entirety of the MG. A correlation between terminations is abstractly expressed as context. A context may include multiple terminations. Therefore, relations between terminations are depicted by a topology. A termination not correlated with any other termination is included in a special context called “null”.
Based on the foregoing abstract connection model, the interactions between the service and the bearer may be regarded as operations for the termination and the context. Such operations are performed through command requests and replies between the MGC and the MG. The types of commands include: Add, Modify, Subtract, Move, Audit Value, Audit Capabilities, Notify, and Service Change. Command parameters, also known as descriptors, are categorized into property, signal, event, and statistic. For convenience, the parameters correlated by a service aggregate into a package logically.
The control exercised by the MGC over the MG may be intended for a termination or streams on the termination. With respect to exercising control over the termination, non-stream features (such as service state and event buffer control) on the termination are included in a termination state descriptor; with respect to exercising control over streams on the termination, stream features on the termination are included in a media descriptor, and a media descriptor may include several stream descriptors. Each stream descriptor is intended for a single stream, and includes a local control descriptor, a local descriptor, and a remote descriptor. A local control descriptor includes stream-related control information, for example, Mode, Reserve Group, and Reserve Value. A local descriptor includes the features of the streams received locally, and a remote descriptor includes the features of the streams received remotely. For example, the features are address, port, coding algorithm, and decoding algorithm, and so on, which are described through a Session Description Protocol (SDP).
Under the control of the MGC, the MG may interact with other devices such as User Agent (UA) representative of the user to distribute information to the user or collect information from the user. In some service scenarios, the MG plays a type of media to the UA under control of the MGC, for example, plays a voice prompt or a Video On Demand (VOD) program. Meanwhile, the user can control the play of the media in a certain mode such as Dual-Tone Multi-Frequency (DTMF), for example, through operations such as play, stop, pause, resume, fast forward, and rewind, which are similar to the operations on a Video Cassette Recorder (VCR). The user input is resolved by the MGC. The user input is received by the MG and the media play is controlled by the MGC. Therefore, the MG generally notifies the user input to the MGC, and the MGC instructs the MG to control the media play. In an actual environment, the control operations such as play, stop, pause, resume, fast forward or rewind in the process of media play do not involve change of the media (namely, do not involve change of media resources). Therefore, if the MG can perform such control operations independently without the interference of the MGC, the control will be more simple and efficient. However, with the MGC being separated from the MG in the current architecture, no solution is disclosed to enable the MG to control media play independently according to the DTMF input of the user.
In the prior art, with a media resource server environment of a split architecture, when the media resource controlling device and the media resource processing device interact with the user to control media play, or when the media control function device and the media delivery function device interact with the user to control media play, no solution is disclosed to enable the media resource processing device or the media delivery function device to control the media play independently according to the DTMF input of the user.